Question: Simplify the following expression: $ n = \dfrac{2}{7} + \dfrac{-8a + 1}{2} $
Solution: In order to add expressions, they must have a common denominator. Multiply the first expression by $\dfrac{2}{2}$ $ \dfrac{2}{7} \times \dfrac{2}{2} = \dfrac{4}{14} $ Multiply the second expression by $\dfrac{7}{7}$ $ \dfrac{-8a + 1}{2} \times \dfrac{7}{7} = \dfrac{-56a + 7}{14} $ Therefore $ n = \dfrac{4}{14} + \dfrac{-56a + 7}{14} $ Now the expressions have the same denominator we can simply add the numerators: $n = \dfrac{4 - 56a + 7}{14} $ $n = \dfrac{-56a + 11}{14}$